How should you structure a Next.js project?

Structuring a Next.js project might seem straightforward at first, especially since Next.js comes with a lot of conventions out of the box. However, as your application grows, a well-thought-out folder and file organization becomes crucial for maintainability, scalability, and developer productivity. Over the years, I’ve worked on multiple Next.js projects ranging from small marketing sites to large-scale SaaS platforms, and I’ve learned that the right structure balances convention with flexibility.

Below, I’ll walk through practical advice on how to structure a Next.js project, including core concepts, real-world examples, common pitfalls, and performance considerations. I’ll also touch on security and interview tips, so you’re well-prepared to discuss this topic in a technical interview or apply it in production.

Core Concepts Behind Next.js Project Structure

Next.js is built around the idea of convention over configuration. The framework expects certain folders like pages and public to exist and uses them to automatically generate routes and serve static assets. However, beyond these conventions, you have the freedom to organize your components, utilities, styles, and API routes in a way that suits your team and project size.

Here are some key folders and files you’ll encounter in a typical Next.js project:

• pages/: Contains React components mapped to routes. Supports file-based routing.
• public/: Static assets like images, fonts, and robots.txt.
• components/: Reusable UI components.
• styles/: CSS, Sass, or other styling files.
• lib/ or utils/: Helper functions, API clients, and shared logic.
• api/ (inside pages/): Serverless API routes.
• hooks/: Custom React hooks.
• contexts/: React context providers for global state management.

While Next.js doesn’t enforce these beyond pages and public, adopting a consistent structure helps keep your codebase clean and scalable.

Example of a Scalable Next.js Project Structure

Here’s a practical folder structure I’ve used in production projects that balances clarity and scalability:

/
├── components/
│   ├── Button/
│   │   ├── Button.tsx
│   │   ├── Button.module.css
│   │   └── index.ts
│   ├── Header/
│   └── Footer/
├── contexts/
│   └── AuthContext.tsx
├── hooks/
│   └── useAuth.ts
├── lib/
│   ├── apiClient.ts
│   └── helpers.ts
├── pages/
│   ├── api/
│   │   └── auth.ts
│   ├── _app.tsx
│   ├── _document.tsx
│   ├── index.tsx
│   ├── dashboard.tsx
│   └── profile/
│       └── [id].tsx
├── public/
│   ├── images/
│   └── favicon.ico
├── styles/
│   ├── globals.css
│   └── variables.css
├── types/
│   └── index.d.ts
├── .env.local
├── next.config.js
└── package.json

Let me explain some choices here:

• Component folders with index files: Each component lives in its own folder with styles and tests (if any). This keeps related files together and makes imports cleaner (import Button from 'components/Button').
• Contexts and hooks: Separate folders for React contexts and custom hooks help organize state management and reusable logic.
• Lib folder: Contains shared utilities, API clients, or anything that isn’t a React component but is used across the app.
• Pages folder: Follow Next.js conventions strictly here. API routes go under pages/api. Dynamic routes like [id].tsx are used for user profiles or similar.
• Types folder: For TypeScript projects, centralizing types improves maintainability and reduces duplication.

Why This Structure Works Well

This approach works because it separates concerns clearly. Components are self-contained, making them easier to test and reuse. Hooks and contexts are isolated, which helps when you want to refactor or swap out state management solutions. The lib folder keeps your business logic or API clients decoupled from UI code, which is great for testing and scaling.

Also, by keeping the pages directory clean and focused on routing, you avoid mixing UI components with routing logic, which can get messy fast in larger projects.

Common Mistakes When Structuring Next.js Projects

• Dumping everything in pages: Sometimes developers put all components directly inside pages, which bloats the folder and makes it hard to find reusable components.
• Over-nesting folders: Deeply nested folders might seem organized but can make imports verbose and navigation painful.
• Ignoring naming conventions: Inconsistent naming (e.g., mixing camelCase and kebab-case) can confuse developers and cause import errors.
• Not separating API routes: Mixing API route logic with UI components leads to tightly coupled code and harder maintenance.
• Skipping type definitions: For TypeScript projects, not centralizing types can cause duplication and type drift.

Performance Considerations

Next.js optimizes performance through automatic code splitting and server-side rendering (SSR). Your project structure can impact how effectively these features work:

• Keep components small and focused: Smaller components mean smaller chunks and faster load times.
• Lazy load heavy components: Use dynamic imports (next/dynamic) for components like charts or maps that aren’t needed immediately.
• Static assets in public: Store images, fonts, and other static files in public to serve them efficiently via CDN.
• Optimize API routes: Keep serverless functions lightweight and avoid heavy computations inside API routes to reduce cold start latency.

Security Considerations

While project structure doesn’t directly enforce security, organizing your code properly helps avoid common pitfalls:

• Separate client and server code: Keep API routes and sensitive logic in pages/api or lib to avoid accidental exposure.
• Environment variables: Use .env.local for secrets and never commit them to version control.
• Validate inputs in API routes: Since Next.js API routes are serverless functions, always validate and sanitize inputs to prevent injection attacks.
• Use HTTPS and secure cookies: Configure your hosting environment to enforce HTTPS and secure cookie flags.

Interview Tips When Discussing Next.js Project Structure

• Explain trade-offs: Interviewers appreciate when you talk about why you chose a certain structure, not just what it is.
• Mention scalability: Show awareness of how your structure supports team growth and codebase expansion.
• Discuss conventions vs customization: Next.js has defaults, but you should explain when and why you’d deviate.
• Bring up testing: Mention how your structure facilitates unit and integration testing.
• Highlight performance and maintainability: Talk about how your structure impacts build times, bundle sizes, and developer onboarding.

Comparison With Other Project Structures

Aspect	Flat Structure	Feature-Based Structure	Domain-Driven Structure
Description	All components and pages in one or two folders.	Group files by feature or functionality.	Organize by business domain or bounded context.
Pros	Simple, easy to start.	Improves modularity, easier to scale.	Aligns with business logic, good for large apps.
Cons	Becomes messy quickly.	Can lead to duplicated utilities.	Requires upfront domain knowledge.
Use case	Small projects or prototypes.	Medium to large apps with clear features.	Enterprise-level apps with complex domains.

Personally, I prefer a hybrid approach: feature-based organization for components and pages, with shared utilities and hooks centralized. This keeps things modular but avoids duplication.

Practical Production Scenario

In one SaaS project I worked on, we started with a flat structure but quickly ran into issues as the app grew. We refactored to a feature-based structure where each feature folder contained its pages, components, hooks, and tests. For example:

/
├── features/
│   ├── auth/
│   │   ├── components/
│   │   ├── hooks/
│   │   ├── pages/
│   │   └── api.ts
│   ├── dashboard/
│   └── profile/

This made onboarding new developers easier because they could focus on one feature at a time. It also improved our CI build times since we could run tests and linting per feature folder.

We kept global styles and shared components in their respective top-level folders. This balance helped us maintain clear boundaries while sharing common code efficiently.

Summary

Structuring a Next.js project isn’t just about following conventions; it’s about setting up your codebase for long-term success. A clean, modular structure improves maintainability, helps with performance optimizations, and makes scaling your app and team easier. Avoid dumping everything into pages or components, and think carefully about how your project will grow.

When preparing for interviews, focus on explaining your reasoning, trade-offs, and how your structure supports real-world challenges like testing, performance, and security. Sharing concrete examples from your experience will always stand out.